Research On Technology Of Detecting Phase-to-ground Fault In Ineffectively Grounded System And Its Single-chip Device

The devices for detecting phase-to-ground fault in ineffectively grounded systems are seldom functionary at present. Based on thousands of experiments in high-voltage laboratory in north china electric power university, the reasons for misjudgment and the effective measures to avoid it are presented in this paper: to change PT connection form to prevent from ill-effects of ferro-resonant overvoltage ;to increase soft measures to resist against interference; to adopt Neural Network method to obtain the virtual value of the detect way . All of the above measures are all tested by the experiments.In our country, auto-reclose technology hasn't been applied in ineffectively grounded systems. The paper gives the evidences for making use of auto-reclose technology in ineffectively grounded systems from its importance, feasibility and validity.To develop the single-chip microcomputer of the device, the paper does a lot of work of design hardware and software include using soft timer with task-plan solving the whole arrangement of the process.